There are a diversity of devices and methods for transforming an infusible beverage substance such as ground coffee into a tasty, hot drink. Many attempts have been made to facilitate the preparation of a single cup or limited number of cups of a hot beverage such as coffee in an efficient and tidy manner.
U.S. Pat. No. 3,833,740 to Schmidt discloses a single portion coffee pack. The pack constitutes a permeable filter defining a chamber containing ground coffee which can be immersed in a cup or pot of hot water. Coffee is brewed in much the same way tea is with a tea bag. Water permeates in and out of the pack, extracting edible, soluble food solids from the ground coffee. An external sheath preserves freshness of the pack contents until the sheath is removed manually just prior to immersion of the pack in hot water. The pack contains, beneath the coffee chamber, an air pocket. When the pack is immersed in water, air escapes from the air pocket upwardly into and through the chamber containing the coffee, agitating and turning the coffee. This enables the hot water to contact a greater surface area of the ground coffee, facilitating a more effective penetration of the coffee and a quicker extraction of the edible food solids from the coffee. Agitation is minimal, however, and a more effective beverage infusion device is highly desirable.
U.S. Pat. No. 4,410,550 to Gaskill involves a similar attempt to prepare a single cup of coffee by air agitation in an air-water chamber. Ground, roasted coffee is enclosed in a chamber permeable to air and water. A conduit or tube is connected to the bottom of the chamber, with the connected end covered by a mesh material to prevent entry of ground coffee from the chamber into the tube. The tube extends up alongside the chamber to a point above the water level of a normal cup of coffee. Once the chamber is immersed in hot water, the user blows through the tube and air flows through the tube into the chamber and through the ground coffee, "violently carrying coffee particles and water solubles with it." While the Gaskill invention promotes a more efficient brewing process, ultimately, the effectiveness of the device resides with the user, who must develop through trail and error the proper amount and velocity of air to send shooting through the air conduit and hence into the chamber. Too much enthusiasm and the user can burst the walls of the chamber from within, spill water, or produce similar undesirable results.
Accordingly, the need still exists for a device and method of brewing a single cup or limited number of cups of a hot beverage such as coffee which will not require the user to develop any special technique and will effectively and efficiently permit extraction of the soluble food solids from coffee and the like to the water, thus providing a delicious hot beverage.